Hotchkiss No Limits 2016

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LIMITS NONO LIMITS The Hotchkiss Science & Technology Magazine

Winter 2015

The Hotchkiss Science & Technology Magazine Winter 2016

FATE OF THE Y-CHROMOSOME

MICROBIOMES

SOCCER OUR INTESTINAL ALLIES STATISTICS

THE INVISIBLE CLOAK NOT ALL IT’S CRACKED UP TO BE THE DISEASE OF ADDICTION

THE POWER OF MUSIC

‘PSYCHIC INCOME’ AND THE

SEARCH FOR ET AN INTERVIEW WITH SETH SHOSTAK


CONTENTS

04 Artificial Intelligence 06 Can Siri find Aliens? 08 Nepali Climate Crisis 11 Soccer Statistics 14 The Power of Music 16 MERS Outbreak in Korea 18 Fate of Y-Chromosome 20 Aerodynamics in Endurance Sports 22 Elephant’s self-defense against Cancer 24 Neuroscience of Religion 28 Necrotizing Fasciitis 30 Pressure and Related Experiments

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FROM THE EDITORS When No Limits published its first issue in 2012, our founders aimed to provide a “niche” for our students interested in science, technology, engineering and mathematics. We continue to believe that providing an opportunity for STEM students to write about their academic passions is incredibly important. Staying true to the founding goals of the magazine, we hope this issue will contribute bridging the gap between the science classroom and the real world. The topics that fellow writers have shared in this issue range from Soccer Statistics to discussion of epidemics. This broad spectrum of ideas illustrate the great volume of inspiring information that remains unknown to the public. Each day, many of us find ourselves particularly struck by an innovative technology or scientific concept in the news. Our writers contributed their articles with the desire to share this fascination and excitement with the wider community. Thus, in presenting this fine collection of STEM-writing to all Hotchkiss students, faculty and staff, we hope to share glimpses of the world of science that can enlighten all of us. We are always looking for writers willing to explore the world of science and technology. Anyone dedicated to the discussion of these fields is always welcome. Viola and Elaine

Editors-In-Chief Viola Lee ’16 Elaine Wang ’16

Editorial Board Chimdi Alagor ’16 Bobby Kwon ’16 Elisa Xu ’17 Carina Zhang ’16

Art Editor Sumin Goh ’18

Marketing Team Jack Duryea ’16 Daniel Kim ’18 Jay Lee ’18

Contributing Writers Sean Doolan ’18 Jack Duryea ’16 Daniel Kim ’18 Jay Lee ’18 Sue Lee ’18 Rebecca Li ’16 Jackie Ryu ’17 Sam Saxena ’17 Amy Wang ’19

Faculty Advisor Dr. Susan Park

Visit us online: hotchkissmedia.org/nolimits

Like us on Facebook: facebook.com/hotchkissnolimits

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Artificial Intelligence BY CHIMDI ALAGOR ’16

When the average person thinks about artificial intelligence, his mind probably wanders to Terminator, not Netflix. While humans are currently decades away from creating a sentient robot, the field of artificial intelligence (AI) has advanced rapidly and noticeably. Facebook’s facial recognition feature, Google’s selection of the most relevant results, and Netflix’s recommendation engine each easily complete a task that was incredibly difficult a few years ago – improvement without human input. The recent hype surrounding artificial intelligence focuses on a particular subfield called deep learning, a process in which a system analyzes large sets of data to recognize patterns and eventually teach itself certain tasks. Modeled on the brain, deep learning algorithms mimic the body’s network of neurons and the interneuron connections that strengthen with use. The algorithm organizes neural nets, made of simulated neurons, into stacked layers; the first layer find the lowest level patterns then passes the information to the next layer in order to find increasingly complex patterns. Starting with the realization that all faces have eyes, the algorithm might recognize that most faces have two eyes, and then recognize that two eyes usually accompany a nose, and eventually recognize a whole face. This method of learning resembles the way that human babies learn to perceive the world— they start with the simplest patterns and work their way up.

The basis of deep learning is not a new concept. Researchers developed the first neural nets early in the 1950s, during the initial wave of AI research. However, these primitive programs required someone that could manually feed them information and rules that could help them identify objects. Even after this time-consuming effort, these neural nets still did not have enough simulated neurons or computational power to analyze complex patterns. The current level of advancement in deep learning has been made possible by the convergence of two byproducts of our increasingly technological world: massive amounts of data and cheap parallel computation. The information produced by the world’s constant connection to the internet has exponentially increased the amount of electronic data in existence. Just as children need examples to train them to identify different animals, computers need data to train them to identify patterns. Parallel computation, often used in video game systems, divides large tasks into smaller ones, which are then completed simultaneously and hastens the process of computing large data sets. At first glance, the impact of deep learning might seem constricted to only technological companies. However, the fundamental goal of deep learning, to recognize trends and learn tasks, coincides with a myriad of industries and jobs. Industries like finance, medicine and security can im-

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© University of Chicago


mensely benefit from the data analysis that deep learning can provide. In 2012, the pharmaceutical company Merck held a contest that rewarded any team that could beat its best programs in finding potential drug candidates; a team of researchers from the University of Toronto won first place and $22,000 with a deep learning system. A trading firm startup, Binatix, uses its deep learning algorithms to find patterns that can give the company an advantage when making investments, and has become profitable within its first three years. Chinese search giant, Baidu uses deep learning to recognize threats before they become significant and to predict hard drive failure a day in advance. Unfortunately, the benefits of deep learning and AI also come with downfalls. The field continues to advance rapidly; soon, and for a fraction of the cost, algorithms will replace many of the jobs formerly reserved for humans. For example, Skype’s natural language processing program can now translate language in real time. Although this program is not completely accurate, it will only improve with time, and it is significantly cheaper than a human interpreter, which can cost between $50 and $145 an hour. In a few year’s time, automated cars, which currently use computer vision based on deep learning, could make the job of a bus driver nonexistent. The transportation industry currently employs about 4.5 million people. How would the near simultaneous loss of millions of jobs affect the economy? In addition to the potential for human replacement, the recent rise of AI also raises novel ethical questions. How should an automated car react when faced with the small potential for human injury versus large vehicle damage? Normally, car drivers must make split-second decisions in times of distress and therefore cannot be held accountable during these moments. However, a programmer needs sufficient time to analyze and weigh the benefits of a decision made in distress, before the distress even occurs. The pace at which the world produces data will continue to increase with time. With deep learning, the insights that algorithms can draw

from this data can be used to revolutionize our world and notice trends previously imperceptible to the human eye.

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CAN SIRI FIND ALIENS? BY JACK DURYEA ’16

How do astronomers search for life in the universe? Despite the unprecedented discoveries made by probes such as the Martian rover Curiosity, the distances to planets in other solar systems are too extreme for firsthand exploration. Scientists thus resort to telescopes and other optical tools to search for life-filled planets. Binary star systems are strong candidates for supporting habitable planets. In fact, it is estimated that nearly 50%-60% of binary stars provide the necessary factors to serve as hosts. This semester, I have worked on a computer simulation that models the behavior of these types of star in the hopes that this model could one day aid in the discovery of extraterrestrial life. Imagine playing tug-of-war against your friends. Now imagine a star playing tug-of-war against another star. This is a binary star system; two stars bound together by a gravitational rope while orbiting around each other. Because of this orbital behavior, the two stars will take turns moving towards, and then away from the observer. This activity creates what is known as a Doppler shift, a stretching and compression of the wavelengths in a beam of light. These shifts become apparent when we observe the star’s emission spectrum, which is essentially a rainbow-like diagram that displays the chemical elements 6 • No Limits • Winter 2016

present in a star. Thus, by analyzing the star’s spectrum and the associated red-shifts and blue-shifts, we can determine not only the chemical composition of the star, but also its distance, radius, temperature, orbital period, etc. The aforementioned computer simulation allows the user to input data on the star such as its spectral type, mass, size, etc. With knowledge of what characteristics life-supporting binary stars possess, scientists can input these parameters into the simulation. Given the input data, a visual model is constructed, simulating the motion of the stars around their orbits as well as the spectrograph that results from the red-shifting and blue-shifting of the stars relative to the earthling observer. As the simulation runs, spectroscopic data is generated both visually and numerically. This computer model can be used to determine what types of spectra to look for when searching for life in binary star systems and could serve as a powerful tool in making predictions about which star system contains the next Earth. Perhaps one day, instead of solving equations on chalkboards, scientists will be able to sit down with a cup of coffee, pull out their iPhone and ask “Hey Siri, is there any life out there?”


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NEPALI CLIMATE CRISIS BY JACKIE RYU ’17 Climate plays a key role in determining the health, safety, and economic productivity of individuals in developing countries around the world. Of the dozens of countries that have constantly suffered from natural disasters, Nepal garnered my highest attention due to the fact that its frequency of catastrophic events has been increasing at an alarming rate in the last decade. But will the nation fall victim to ineluctable destruction, or are chances for the better? To gain a thorough insight, my research partners and I utilized Python and several of its librarie: scipy, numpy, matplotlib, etc to cross-reference a total of 5 reputable models from CMIP5 and create graphical representations of the multi-model mean. Upon processing the data, we observed an average 1.5 to 3.5 degrees Celsius increase in average temperature, a 2.5 to 4 degree increase in extreme temperature, and a 5-15mm/day increase in precipitation from 2041 to 2060. Notably, the most affected regions from the projections were the 8 • No Limits • Winter 2016

higher elevations, mainly mountainous, suggesting that glaciers would become highly vulnerable to a rapid meltdown; not only does this remove a major source of Nepal’s water supply, but also damages its tourism-centered economy. This proves the urgency for a collective call to action, as without unanimous support from the international community, Nepal is likely to face significant economic disruption and human suffering over the coming decades. Nepal, due to its unique geographical location in the Himalayas, is subject to a variety of extreme climate events. Nepal, as of 2015, faces various threats to the stability of its climate. Its 2009 winter droughts have already compromised its food security by producing a national decrease in wheat and barley production by 14.5 and 17.3 percent, respectively. Due to the extensive flooding and landslides in the summer of 2014, more than 225,000 people were affected and 10,000 houses were partially destroyed (IFRC 2014). Moreover, according to the Nepal Disaster Report 2013, from 1971 to 2012,


6627 incidents of landslides and floods have been reported and a total of 8590 deaths have occurred. In a nation where agriculture contributes to more than a third of its Gross Domestic Product, the continuum of such events will lead to severe circumstances such as an extreme inflation of food prices and even shortages in certain areas. Over 75% of the Nepali labor force hold occupations in the agricultural sector (CIA 2013-2014) and the share of services in its economy has increased to 49.76% in 2011(Nepal Ministry of Home Affairs, 2014). Both the growth of crops and the number of tourists are highly depend on weather; such reliance on climate sensitive industries prompts the weather to have a significant impact on the nation’s economy and social infrastructure. In light of Nepal’s primary economic dependency on stable climate, recent anthropogenic climate change will likely have appalling consequences for its citizens. Such detrimental effects of natural disasters in Nepal are further exacerbated by the insufficiency of government infrastructure as demonstrated in the recent (2015) 7.8 earthquake in Nepal. It resulted in the death of 9000, a casualty attributed to the Nepali government’s lack of natural disaster management capabilities in addition to the abysmal quality of housing, poor access to information, and improper allocation of international aid. While Nepal has abundant water resources,

due to natural precipitation cycles and mismanagement, water becomes scarce in some regions during the dry season. As climate change shifts rainfall patterns and enhances extreme events, functional and effective water management will become even more essential. It is important that the Nepali government focus on how climate change may influence precipitation in the coming decades and how to best mitigate the potential societal impacts. Climate projections are made using general circulation models (GCMs) which attempt to simulate all known physical processes in the climate system. These range from atmospheric dynamics -- the transport of mass and moisture through the atmosphere, driven by unequal heating and the earth’s rotation -- to thermodynamics to landsurface processes which affect and are affected by the broader climate system. In a climate model, the world is broken down into grid boxes in the range of 2x2 degrees latitude/longitude. The resolution of models varies, but few drop below 1x1 degree -- however, as the supercomputers that are used to run these models improve, resolution will increase. As global emissions of greenhouse gases accelerate, global temperatures are projected to continue rising at an increasing rate. The world has currently experienced about 1 degree Celsius of mean warming (IPCC, 2013), and further increases of 2-4 degrees are likely by the end of the century (Horton et. al. 2015). This rate of climate change far

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exceeds those from the last million years, and will likely result in tremendous challenges to societal stability in some regions. Precipitation in Nepal is driven by the South Asian monsoon (Annamalai, H., et al, 2007). The monsoon historically brings a period of heavy precipitation lasting from June through September in Nepal. Nepali society is in many ways organized around the start and

end of the rainy season. Changes in the timing of the onset of the monsoon have been known to cause significant disruption to agriculture and the economy, as occurred in 2005 and 2006 when an early start to the monsoon caused reductions in crop yields of 10-15% in the region of Eastern Terai. In other regions during that same year, however, the monsoon rainfall was unusually heavy, and resulted in crop yield declines of up to 30% (Regmi, 2007). While analyzing the trends for precipitation events as well as baseline temperature, the effects of monsoons are not represented accurately in climate models due to their highly unpredictable nature. We investigated extreme precipitation events in the context of their impacts on individuals’ health, safety, and the broader Nepalese economy. We showed projected changes in mean and extreme precipitation between 2041 and 2060 relative to

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a reference period of 1980 to 2004 using the latest generation of general circulation models from the Coupled Model Intercomparison Project Phase 5 (CMIP5, Taylor, K. E., et al, 2004) running under the RCP8.5 emissions scenario, which assumes continued rapid growth in global greenhouse gas emissions through the end of the 21st century (Moss, R., et al, 2010). Current global emissions most closely track this scenario; however, changes in global energy use and policy could result in lower or higher emissions in the coming decades. We choose 2041 to 2060 as our future period because it is a reasonable time interval for which people plan infrastructure projects. Additionally, climate change up to this period is relatively locked in -- that is, even if emissions are significantly reduced in the coming decades, the reduced rates of climate change will likely not be observed until later in the 21st century, thereby reducing the uncertainty in our projections (IPCC, 2013). Using general circulation models from the Coupled Model Intercomparison Project Phase 5 (CMIP5), we projected changes in temperature and precipitation across Nepal that may occur by mid century relative to a base period of 1985-2004. Our results show general agreement with previous modeling studies but with increased certainty: an increase in baseline temperature by 2.5 to 4 degrees, an increased fluctuation in daily precipitation ranging from 5 to 15 mm, and a significant increase in the frequency of all precipitation events, especially the heaviest. All of these projected changes are likely to be detrimental to Nepal’s already declining economy, as the country depends primarily on agriculture for sustenance and well-preserved icecaps for its largest source of revenue -- tourism. Although our projections have room for error, as all projections do, it is without a doubt that the unfortunate reality of worse things to come for Nepal has been well established.


SOCCER STATISTICS BY DANIEL KIM ‘18 WHY CARE? The association of sports with numbers has increased over the years, especially after the success of Billy Beane with his “moneyball” Oakland Athletics. Billy Beane used data to maximize the results he could achieve with the least monetary investment, and when a big team like Red Sox utilized his “moneyball” method, it won the World Championship in 2004. Some skeptical soccer players and managers, however, argue that soccer is too complex for any analysis to have a huge impact. They point at the fact that there is no similar case of an analytical underdog soccer team winning a domestic

league or international championships. However, it is important to realize that as complex as the game is, data analysis techniques of soccer have evolved rapidly recently, and that the adaptation of the analysis in the game has improved through overcoming initial failures. Now every big club has a data department and is contracted to sports data company like Opta, and whether we realize it or not, more and more soccer games are being affected by the growing importance of data analysis. So let’s jump into some interesting insights into soccer gained through analyzing data. The study in soccer analysis has much more to say, but perhaps the fact that half of soccer games are won by luck should be enough to intrigue you to read further. LUCK GIVE YOU WINS AS MUCH AS SKILL How would you feel if I told you that 50% of professional soccer matches are won or lost depending on luck? Before jumping to conclusions, first look at these cases. On October 17th,2009, Benitez’s Liverpool lost to Sunderland by a goal by Darren Bent that took a deflection off a large red beach ball. In another case, a Polish striker Adam Czerskas scored from twenty-five yards with his back. These

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are only some extreme cases of luck contributing to goals, wins, and sometimes major victories in soccer games. A deflection off a defender, a misled clear, a slip of foot with the ball, and much more all frequently contribute to the results of soccer games. A simple way of demonstrating how much luck contributes in victories is by examining the percentage of goals scored by accident--where the shooter meant to score, but the goal only became possible through a random and uncontrollable event. Martin Lames, a Professor of Training Science and Computer Science in Sport at the Technical University Munich, conducted research precisely on this topic, and discovered that of over 2500 goals, 44.4 percent was determined by luck. This probably isn’t too surprising when we consider the data from 2010/2011 sports leagues which shows that pre-match favorites of soccer only won 52~53% of the time, while the favorites of handball, basketball, and football all won more than 60% of the time. A similar study by Redner, Ben-Naim, and Vazquez of more than 43000 games shows that the underdogs of soccer win 45.2% of the matches. More direct evidence comes from Skinner and Freeman’s research. They determined that if match outcomes directly mirrored a team’s skills, then there won’t be a case where Liverpool beat Tottenham, Tottenham beat Everton, but Everton beat Liverpool. They dubbed such cases as“intransitive triplets” and by looking at the World Cup games, found out that among 147 games where none was a draw, 12% were intransitive. When you consider that the expectation of intransitive games is 25% if you suppose games are determined purely by chance, this means that 48% of the games were determined by chance, not skill. EFFECTIVENESS OF SET PLAYS Whenever there is a corner or free kick, people rile up as the anticipation for a goal rises. With the box piled up with players and a free given cross, 12 • No Limits • Winter 2016

surely a lot of goals should come from corners! But as it turns out, data from the sample of 134 of 2010/2011 EPL games show that the success rate of a corner to a shot on goal is only 20.5%. Of those shots on goal, only one in nine is converted into a goal. Chris Ander tells us that these data show how an average corner is worth only 0.022 goals. Every time a corner happens,we see defenders moving up into the opponent’s box and players framing the box, regardless of the counterattack threats, because t h e team believes in getting a chance out of corners. Would they act similarly if they knew that the average corner is only worth 0.022 goals, though? We must, however, acknowledge that t h e number varies when we look at different tiers of soccer. Take Hotchkiss’ JV soccer, for example, which managed to convert two out of twentythree corners so far this season--a conversion rate of 0.087--had almost four times the conversion rate of corners in EPL (But because of a small sample, there is a greater chance of error in utilizing Hotchkiss data.) Either way, these numbers are useful in advising coaches whether to change their approach on corner kicks or stick with the traditional methods. The effectiveness of free kicks is also hard to measure because of the rarity of goals that result from it, but the data tells us that an average 2010/2011 EPL team needed thirty-five direct free kicks to score one goal. Likewise, Hotchkiss JV team had 18 direct free kicks, in which none had led to a goal. More goals result from indirect free kicks, but without any significant differences. As with corner kicks, the so feared free kicks are as useless in producing goals. But then, the effectiveness of set plays can differ depending on the player’s team, and the player’s indi vidual aims or goals (no pun intended). For example, in the case of Atletico Madrid, the


team put in thirty goals through set plays among the sixty seven goals it scored in the league during the 2014/2015 season. When a team is struggling to converting goals, focusing on set play practices and maximizing set play chances could actually be a method, as Atletico proved by clenching the third place in the Liga table this 2014/2015 season. Set plays also take a longer time to execute than most open plays, which means that if used correctly, set plays could be a defensive method of not playing the game at all. Take Stoke City under Tony Pulis, for example, which managed to play the least amount of actual soccer in the Premier League for years by playing long ball. This meant that they reduced the chances of conceding along with the actual playing

time and therefore, over performing with smaller budgets. The analysis of soccer statistics has much more in context. For example, there are percentage data of how likely a team with the first goal is likely to win a match, whether a team that scores more or concedes less is likely to win the league, and so on. Delving deeper into this field breaks prejudices about soccer that we might have had, and also shines light on new aspects of soccer that no one paid attention to before. If this article intrigued you, maybe you could do more research by yourself. Websites like http://www.whoscored.com offer detailed statistics of every major team and major match, which you might be able to utilize.

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THE POWER OF MUSIC BY ELISA XU ’17

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ven before the age of Justin Bieber, music has been an active component of our lives. Whether it acts as a pump up track you work out to or a self pity tune to justify the teenage angst, music has shown to significantly affect our moods. Jamming out to Beethoven or EDM may not be too different after all. Listening to a song that we love is essentially a visceral experience. It can drown out our bodies’ complaints of fatigue while we are exercising. In 1911, an American researcher, Leonard Ayres, discovered that cyclists pedaled faster when listening to music than when they rode in silence. When our bodies start to tire, our muscles send signals to the brain to take a break from exercising, and listening to music competes for our brain’s attention. Additionally, music can help us use our energy more efficiently. A 2012 study showed that cyclists who listened to music needed 7% less oxygen to accomplish the same work in comparison to those who cycled in silence. There seems 14 • No Limits • Winter 2016

to be a ceiling effect on music around 145 bpm, where anything higher doesn’t affect our motivation to exercise as much. Nevertheless, finding the right song to run to may contribute to our work-out success. The power of music is evident, but it is to a greater extent than you may have thought. According to the award winning physician and author Oliver Sacks, music can act as a “Proustian mnemonic, eliciting emotions and associations that had been long forgotten, giving the patient access once again to mood and memories, thoughts and words that had seemingly been completely lost.” Additionally, Dr. Sacks commented on how music can aid patients with advanced dementia in re-establishing a more concrete reality because “musical perception, musical sensibility, musical emotion and musical memory can survive long after other forms of memory have disappeared.” Music appeals to our emotional sides that are shown to persevere even when our ability to reason are lost – similar to other forms of art, it can stir certain feelings


“WITHOUT M U S I C, L I F E WOULD BE A M I S TA K E.”

that words may fail to eloquently describe. Unsurprisingly, music is not only capable of moving us in specific emotional moments, but also triggering feelings that may teach us about our unconscious. For instance in a case study by PsychCentral, Cyndi, a woman in her mid-30s has struggled through years of depression. Although she normally listened to music that aggravated her sadness, she also found a passion for energetic music that released her from the imprisonment of her depression. It turns out that Cyndi was an energetic child before her mother died after a brief illness when Cyndi was 11, kick starting her struggle with depression and disconnecting her from her happy self. Cyndi realized that listening to upbeat music as an adult prompted her core self to heal itself, regain the lost energy, and reestablish the lost connection with the outside world. Paying attention to our emotional patterns when listening to certain types of music may assist in self evaluation of our “normal” dispositions, and encourage us to broaden our scope of emotional tendencies. Making your own music is also seen as therapeutic: this includes singing, but also, chanting. A

study published in the International Journal of Yoga showed that chanting the word “Om” is almost as effective as implanting a vagus nerve stimulator (VNS). A VNS, which requires surgery and has the possibility of changing vocal cords, is used to treat epilepsy and depression. Both chanting “Om” and the VNS produce limbic deactivation, the opposite reaction of depression. Emily Lewis, a graduate student at the California Institute of Integral Studies who studies sound and healing found that “doing vocal singing sessions is a way to bring you into the present moment and could be correlated to longer telomere lengths.” Telomeres are the end caps of DNA strands, and longer strands are indicated to correlate with both longevity and quality of life. In our digital age, listening to music has become integral to many people’s daily lives. However, does our constant need for noise reflect upon our inability to concentrate in silence, or to be still at all? Perhaps rather than playing your go-to tune, find a moment in the day to hear music in the sound of the rain or heavy footsteps, in ambience, and slow down the modern day racing pace. No Limits • Winter 2016 • 15


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MERS OUTBREAK IN KOREA BY SUE LEE ’18

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f you spent the past summer in Korea, you may have seen a lot of people wearing masks. If you were not aware of the situation in Korea, you would have felt baffled by the fearful atmosphere, caused by a deadly virus, MERS. A deadly contagious disease, Middle East Respiratory Syndrome (MERS) was first detected in camels and humans in the Middle East. Through various animal vectors and human travel, MERS rapidly spread around the world, especially causing havoc in South Korea last summer. Though the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC) have stated that MERS was not a global emergency, it put South Korea in a serious predicament regarding taking care of all the infected hospitals, patients, and other citizens as well. So what is MERS? MERS is a respiratory illness caused by coronavirus, which comes from the same family of viruses that causes the common cold. MERS was first reported in Saudi Arabia in 2012, spreading to other continents such as Africa, Europe, and Asia.Symptoms of MERS include fever, cough, and shortness of breath, which are all similar to symptoms of the common cold. In severe cases, vomiting, injury to organs, and pneumonia may occur. Since MERS can be spread among people who are in close contact with infected patients, especially doctors treating sick patients, the

Korean government decided to quarantine people at home or in institutions to prevent MERS from spreading further. The government also recommended people not to use public transportation to prevent the spread, although the subway and buses constitute a crucial part of most Koreans’ daily lives, as many depend on expedient and cheap modes of transportation to go to work each morning. The government’s other recommendations included avoiding crowds to avoid infection, particularly shopping malls, parks and other public places. International travel from Korea was also discouraged, in order to contain the virus within the Korean borders. Some were advised by district agencies to avoid hospitals. However, despite such efforts to isolate the spread of MERS, hospitals were not responsible enough to keep track of who had been in the emergency room with the initially infected patient and such, possibly infecting others in the community or other hospitals. Further exacerbating the damage, the lethal disease scared away a significant portion of tourists and domestic consumers. Because travel to Korea was internationally discouraged, the Korean economy began to show declining trends. Even though the MERS crisis has finally settled down since the beginning of August, vigilant monitoring is frankly crucial and needed. MERS gave the world a “wake-up call” of how we should keep ourselves clean and sanitized for the preventing ourselves from getting sick.

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FATE OF THE Y-CHROMOSOME BY VIOLA K. LEE ’16

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hen we align our 23 pairs of chromosomes, we are able to spot a conspicuously small chromosome—the sex-determining chromosome, Y. Since its emergence, the Y chromosome has decreased in size throughout evolutionary history; even less impressive than its size is its minimal role in anatomical function, with the least number of coding genes in the entire set of 23. While the X chromosome is the eighth largest chromosome in the chromosome set, accounting for over 5.1% of the protein-coding genes in the genome, the Y chromosome is the third smallest chromosome with only 1.9% of protein-coding genes in the genome. Instead, it is abundant in non-coding repeating sequences (STRs) and seemingly meaningless palindrome “mirror sequences.” For these reasons, the Y-chromosome has frequently been exempt from scientific literature. But regardless of its size and limited role outside of sex-determination, the Y-chromosome is nonetheless significant, capturing recent interest due to claims that it may disappear altogether, further along the evolutionary timeline. From investigating Y-chromosome sequences of different species, researchers concluded that since its emergence, the Y-chromosome has consistently shortened in number of genes and size, amounting to its present size. Skeptics argue, however, that the remaining sequences of the Y-chromosome have been conserved, suggesting that its remains will not continue to shorten. The Y-chromosome wasn’t always a sex-determining chromosome. In fact, early mammals did not have sex chromosomes; we are still unsure of how sex determination in ancestral mammals occurred, but we speculate that environmental conditions like pH and temperature determined sex characteristics. Even now, in reptile species like alligators and turtles, sex characteristics are determined by 18 • No Limits • Winter 2016

temperature at fertilization and embryonic development. “Y” emerged later on—an estimated 3 million years ago, as a result of nondisjunction during duplication of a different chromosome that contained genes coding for male characteristics. “Y” was able to survive because it had paired successfully with the X-chromosome during this process. Because the first “Y” chromosome had not been able to pair up with another “Y,” instead pairing with an “X,” the continued shortening of the chromosome was inevitable. In chromosomes that are paired with an identical counterpart, like the first 22 sets in the human genome, errors in one chromosome can be “revised” using the well-conserved counterpart. The “Y,” however, had no such mechanism of error “revision”—it has been vulnerable to detrimental mutations resulting in deletions of entire sets of genes, and the chances of recovering those traits were slim. The Y-chromosome’s decline was thus to be anticipated—arguably, it was doomed from the beginning, in failing to find its identical pair. Through this process, “Y” has decayed rapidly, leaving only 3% of its initial genes to become its current size and shape. More speculation here—the genes necessary for survival probably translocated to other chromosomes. Professor Graves of National University of Australia claimed in his 2002 Nature article that “at this rate, the Y-chromosome will disappear in 10,000,000 years.” Ten million years may seem long in our transient perspective, but in the evolutionary timeline is a fleetingly short duration. “So are they right?”—Does the shrunk size of the Y-chromosome necessarily portend its complete disappearance? After all, the Y-chromosome, too, must have certain essential genes, namely, the genes that constitute male traits. But part of the prodisappearance argument is that the number of “es-


sential” genes on the Y-chromosome is very small; as long as these few essential genes can be relocated to other chromosomes, the disappearance of the Ychromosome is not just possible, but probable.

er. Among its 78 genes, the Y-chromosome’s active genes are even fewer, about twenty, and among those twenty, only two are essential—the status quo seems favorable to its disappearance.

The Con-Case:

The Pro – Case: Consider other animals that have been more extensively researched. Other animals’ Y-chromosomes contain about 200 genes—among which only one gene, called SRY, has been found definitely to determine male traits. SRY (sex-determining region Y) is unique in its sex-determining role, as well as its synthesis of mRNA but not protein; it also serves as a storage compartment of microRNA, which regulates protein production. A recent publication in the prominent magazine Science astonished the scientific community— Hawaii State University’s research team claimed in their article to have found proof that only two genes were required to create a sperm. The SRY gene was one of the two; the other, by a complex name EIF2S3Y, seemed to be another requirement for successful sperm formation. The research team eliminated all but the two genes from the Y chromosome of a fertilized mouse egg. Astonishingly, the mouse developed without defects AND produced sperm. While the sperm was not quite properly matured, through artificial fertilization, the mouse could produce offspring that also grew without defects and with full reproductive capacity. Thus the research team proved that with only two genes on the Y-chromosome, organisms are capable of fully transmitting required genetic information. Of course, indications for mice do not necessarily prove the same indications for humans. Primates do not have the EIF2S3Y gene on the Y-chromosome; instead, humans have a very similar gene called EIF1AY, with similar functions. Mice genes are involved with initial production of sperm, whereas human Y-genes, when mutated, exhibit lack of sperm production or sperm with two Y-chromosomes. To put it bluntly, if the SRY gene and EIF1AY gene could be relocate to another chromosome, it is entirely possible for the Y-chromosome to disappear altogeth-

The 2014 April Issue of Nature claimed otherwise, arguing that the rapid shortening of the Y-chromosome has been stagnant for the past 25 million years, and will continue to remain stagnant. The team, from MIT’s Whitehead Research Laboratory, had published a similar article in 2012. Their research compared DNA sequences of the Y-chromosome among eight species of mammals, including the chimpanzee, humans, and Old World monkeys. From this comparison, the team found that during the past 25 million years, only one gene has disappeared from the Y chromosome, thus demonstrating an end to its progressive shortening and suggesting a continuation of conserved sequences. As evidence, the team also cited that twelve genes on the Y-chromosome played an important role in synthesizing proteins for the heart, lungs and blood—proof that Y-chromosome’s functions are not restricted to reproduction. Moreover, these protein-coding genes are paired with X-chromosome counterparts, and are thus claimed to be very stable. The debate perseveres—whether the Y-chromosome’s essential genes are few enough to be eventually translocated to different chromosomes, and whether its functions are essential enough to be conserved are still unanswered. What is clear is that the Y-chromosome has undergone a complex biological history to acquire its current form; although it has not rapidly transformed for the past 25 million years, it certainly shows possibility for another set of rapid changes. The Y-chromosome has managed to conserve the most essential genes while losing the bulk; whether it will disappear in the future or remain resiliently is a question that will continue to provoke our imagination. No Limits • Winter 2016 • 19


AERODYNAMICS IN ENDURANCE SPORTS BY SEAN DOOLAN ’18

Ask any cyclist to list a number of things that they believe will help them improve their performance, and many professionals and amateurs alike, will surely list aerodynamics as a factor. This pursuit to get more “aero” by cyclists has gained great popularity in recent years, and is even spreading to other endurance-related sports. But what do these “enhanced” aerodynamics consist of and what allows one to improve them? In the cycling world, manufacturers are continuing to make tighter clothing, streamlined helmets, and slimmer bikes to improve this seemingly vital factor. Professional riders are even known to use wind tunnels to perfect their aerodynamic positions and almost diminish any resistance. The idea behind this movement is that a cyclist who is smaller and closer to the ground makes less contact with the surrounding air, thus saving him/ her valuable energy. But can even the slightest change in positioning or equipment actually shave seconds off the clock? According to Kim Blair of MIT, a sufficient change in position along with new aero equipment can save up to two minutes in a 40-kilometer time trial - sometimes the differ20 • No Limits • Winter 2016

ence between first and last place. Many riders still believe, however, that expensive bikes and gear have no effect on their performance. They argue that this “high-tech” marketing by cycling companies is just a scam to increase profit, and there have been studies that, contrary to Dr. Blair’s results, claim that changes in these factors save no energy while riding. It may also be worth considering the mental advantage that comes with an aero bike, helmet, or suit. The feeling that one may experience when switching to new gear simply creates the sensation of being “fast” or “sleek,” something that could alone result in greater performances. This reasoning provides further logic for those who argue that, physically, aerodynamics are insignificant in races. The craze over aerodynamic efficacy appears to be quickly spreading; it is making appearances in other sports such as running and swimming, where, in similar manner, some have argued that there is no real benefit to slightly improved aerodynamics. It is this argument itself, however, that will only increase the popularity of the “aero revolution” in the world of endurance sports and push them further into the “hightech” industry.


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ELEPHANT’S SELFDEFENCE AGAINST CANCER BY SAM SAXENA ’17

P

eto’s Paradox has stumped scientists for a long time. The paradox observes that there is no clear correlation between the number of cells in an organism and the risk of this organism developing cancer. For example, a human is at approximately 40% risk of developing cancer, while a whale’s risk factor is under 5%. If cancer is caused by the unregulated division of altered cells, then shouldn’t a larger animal with many more cells be at higher risk? This dilemma roused the interest of pediatric oncologist, Dr. Joshua Schiffman, who began to research the low risk of cancer in elephants. Schiffman, along with a team of researchers, worked with The Huntsman Cancer Institute (HCI) in Utah, Primary Children’s Hospital, Utah’s Hogle Zoo and the Ringling Bros. Center for Elephant Conservation to find the elephant’s secret. And on October 8, 2015, the results of their research was published in the Journal of the American Medical Association. The answer to their quandary lay in the TP53 gene. TP53 is a retrogene, which codes for a special tumor-suppressing protein, p53. Retrogenes are genes that modify slightly each time they duplicate. Upon identifying a defective cell, p53 causes the cell to self-destruct. Humans possess two copies of this gene in their genome; elephants, however, possess thirty-eight copies of 22 • No Limits • Winter 2016

“UPON IDENTIFYING A DEFEC TIVE CELL, P53 C AUSES THE CELL TO SELFDESTRUC T.”


TP53. The unique combination of TP53 gene copies in an elephant’s genome allows an elephant’s immune system to more effectively handle faulty cells. Compared to the rate of self destruction of normal human cells exposed to radiation, elephants cells’ rate is twice as fast, and over five times as fast as the rate of Li-Fraumeni cells. Patients of Li-Fraumeni Syndrome have only one active copy of p53, and so have a risk factor of more than 90% of having cancer. This research is still in its early stages, so only further studies

will reveal if p53 is solely responsible for protecting elephants from cancer. Even though research still shows room for improvement, this discovery has opened new doors in the world of cancer treatment and prevention. Hopefully, in the future, the work of Schiffman and his team will yield new treatment methods that can extend cancer treatment and prevention beyond the realms of radiation and chemotherapy.

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Neuroscience of Religion BY REBECCA LI ’16 Religion has long been an intriguing aspect of human life. Exploring the relationships between individual and society, self and the external world, morality and sin, past and future, religion helps us communicate and understand each other with depth in an authentic manner. Often thinking of religious experience as falling into the realm of sociology, anthropology, or cultural studies, it wasn’t until the rise of neuroscience in the 20th Century that we start to wonder its possible connections with the brain, the ultimate commander of all human sensations and ideas. Though our neurological understanding of religion is still fairly limited, technological advance and interdisciplinary discussions in the past decades have allowed us to obtain exciting new knowledge on the subject matter. What scientific reasoning, experiments, clinical data, and personal accounts seem to tell us is that brain and belief influence each other, their relationship extremely complex yet meaningful in our cognition of not only religious experience but in a broader sense, the nature of the conscious mind. 24 • No Limits • Winter 2016

Neuroplasticity explains why we all believe in different things. Under the old assumption about the brain, difference in individual beliefs didn’t seem to make sense at all -- If we share the same stable, unchanging brain structure, aren’t we also supposed to think, reason, and believe in similar ways? Disagreement imply then, that someone, either you or I, must have been “wrong”. But the either-or dilemma is now resolved with the understanding of neuroplasticity, as we prove the human brain to be constantly evolving. In a recent study on the neuroscience of spirituality, researchers injected harmless radioactive dyes into the brain of the subjects to inspect their brain activities during religious practice. A Judeo-Christian female who had been doing prayers for more than 34 years showed increased blood flows in the frontal lobes and language area (i.e. inferior parietal lobe) within the course of several minutes. This is likely due to the nature of Christian prayers as an imaginary communication with God, which would require reactions from parts of the brain responsible for speaking, listening, and language interpretation. An-


other subject quickly showed increased activities in the visual area (i.e. occipital lobe) during his Buddhist meditation, which could be explained by Buddhism’s emphasis on the visualization of the Buddha as a way of achieving enlightenment. However, none of the brain activities of the believers were observed with the atheists when asked to contemplate the idea of a higher spiritual existence. This study, among many others, demonstrates the power of neuroplasticity in wiring or re-wiring our brain according to our personal beliefs, sometimes taking place in only a matter of hours. We now know several brain regions that are influenced by spiritual practice. One of them is the prefrontal cortex, the focus area that covers the front part of the frontal lobes; it showed increased neural activity in experienced religious practitioners than others. While meditations and prayers sometimes involve focusing on the image or idea of certain deities or sacred objects, their ultimate goal of achieving mindfulness also explains the activation of the prefrontal cortex. Though we often tend to think of personal well being as a result of getting what we want and getting rid of what we don’t, neuroscience has recently discovered the nature of happiness to be more directly associated with the prefrontal cortex. We are unhappy because of our “pervasive habit to not pay attention to what we are doing”, and under-active prefrontal cortex causes all kinds of clinical syndromes. On the other hand, with constant strengthening of the prefrontal cortex, people who practice meditations and prayers tend to have a more concentrated, peaceful, and attentive mind. A second brain region related to spiritual practice is the anterior cingulate cortex, the frontal part of the cingulate cortex surrounding the corpus callosum. Especially vulnerable to the aging process, the anterior cingulate is involved in impulse control and emotional regulation. Increased activity

in this part of the brain is a result of its ability to generate the feeling of empathy, compassion, and social awareness. Shocking was the fact that Parkinson’s and Alzheimer’s patients were already experiencing “reduced metabolic activity in the anterior cingulate, and this suggest to us that the meditation technique should slow down the deterioration cause by these diseases” after an eight-week meditation program. [1] Constant activation of the anterior cingulate not only helps reduce our level of fear, anxiety, and anger while maintaining a balance between feelings and thoughts, but also protects us from age-related deterioration, a possible explanation for longevity and healthy mental conditions among religious or spiritual individuals.

No Limits • Winter 2016 • 25


Other observations of the brain during or after meditations and prayers include increased activity in basal ganglia, which controls memory formation, cognitive flexibility, and voluntary movements at the center of the brain, as well as increased activity in the cerebellum, which integrates conscious body movements. These observations demonstrate spiritual practice’s significance in creating mind-body balance and unification. An unusual finding is asymmetric activity in the thalamus among advanced meditators: one side of the thalamus is always more active than the other. Neuroscientists believe that this is due to the thalamus’s function as a “reality-teller” and the altered sense of reality of long-time meditators. Based on our knowledge of neuroplasticity, we understand that the more one believes in, let’s say, the concept of God, the more it becomes neurologically real to that individual. However, God is not a concrete physical object that could be seen, touched, and perceived in the actual world. When the individual’s personal, “subjective” truth does not match up with the “objective” reality, asymmetric activity in the thalamus occurs. One of the most intriguing structures involved in spiritual experience is probably the parietal lobe. While according to the study mentioned earlier, the inferior parietal lobe in charge of language lights up, another part of the parietal lobe, specifically the right superior parietal lobe, tends to show decreased activity during religious prac-

26 • No Limits • Winter 2016

tice. This is a result of the region’s distinct function in trying to “create for u s a sense of ourselves and orient that self” in space. Religion is thought to be driven by our motivation to eliminate discrepancy between the present self and a possible, better, “ideal” self. In order to achieve this goal, we often need to experience a “decentering” process, through which our sense of self is dissolved and extended into a greater mindfulness of others and the universe. In Christianity, the dissolution of self is often marked by a sense of unity with God; In Zen Buddhism, it is represented by an understanding of interbeing and dependent origination; In Daoism, it is defined as a sense of oneness with nature…What major religions seem to share in common is the belief in the removal of an absolute ego in establishing a greater, more complete awareness of spirituality. The task of removing the narrow sense of self, then, falls upon decreased activity of its generator, the right superior parietal lobe. Reducing activities in brain regions like the amygdala that generates anxiety and fear, religious practice significantly increases the dopamine and gamma-aminobutyric acid (GABA) levels in the brain, which leads to lower levels


o f depression and pleasurable feelings. Long-term longitudinal studies for more than thirty years even showed that “individuals who infrequently attended religious services had higher rates of death from circulator, digestive, and respiratory disorders”. Since the very initial stage of human civilization, spiritual experience has served to provide us with a sense of security in the midst of brutal struggle for existence in the natural world. Unlike other animals whose “fight-or-flight response is triggered only as long as the perceived threat is present…humans are able to trigger a biological fear response simply by thinking of danger” thanks to mirror neurons and our theory of mind capacity. Mystical beliefs was able to make sense of concepts like death, suffering, and fear, and offer concrete, reasonable explanations for phenomena or ideals unaccountable to our early ancestors, thus reducing anxiety caused by uncertainty and lack of knowledge. Spiritual experience brings communities together through collective rituals. Individuals with greater internal serenity, empathy, and care for others also tend to be more attractive to the opposite sex and may have passed on religiosity as a heritable trait over time. Various twin studies that have proved monozygotic twins to be more similar than dizygotic twins in their religious beliefs supports the heritable assumption of religi-

osity, while VMAT2 is recently given the name of the God gene and argued to be largely responsible for individuals’ predisposition toward spiritual experience. There is a scientific way of looking not only at religious experience but belief in general. Instead of some ineffable, supernatural connection between the mind or soul and the physical world, our conscious beliefs are subjective due to individual experience variability but at the same time, real and irreducible. They are “a biological phenomenon like photosynthesis, digestion, mitosis…caused by lower-level neurobiological processes in the brain and…realized…as higher-level or system features”, while still managing to maintain a personal, emotional, and “qualitative character(feeling)”. Neuroscience of religion is a new field of study full of uncertainties and unsolved mysteries. The challenge is to get comfortable with the lack of concrete definitions, facts, and theories, and stay motivated even without the opportunity to draw any specific conclusions. Research done on the topic may seem random and all over the place at first, but ultimately they do consist a fairly logical, integrative explanation for what is going on in our brain during spiritual experience – and we are able to further understand ourselves, others, and the way the mind and consciousness function from there.

No Limits • Winter 2016 • 27


NECROIZING FASCIITIS BY JAY LEE ‘18

You’ve recently fell off your bike while you were in the woods and now, you have a cut on your arm. No worries right? You’ll just put some antiseptic on it, maybe even hydrogen peroxide. Then, a scab will form and everything will be better… What if doesn’t? What if a couple days later, you feel fatigued with a burning fever all throughout your body? What if soreness seizes your muscles and it feels like a cramp, although it might not be? What if there is an unbearable pain all throughout your body that doesn’t feel normal for a wound of that size? It’s bad news; you just might have Necrotizing Fasciitis. 28 • No Limits • Winter 2016

Agonizing to say the least, Necrotizing Fasciitis is caused by a variety of different bacteria including A Streptococcus, Escherichia coli, and Klebsiella. A Streptococcus, the main perpetrator and of strep throat usually can be treated easily, but because bacteria involved in Necrotizing Fasciitis is able to penetrate the superficial fascia, a layer of connective tissue below the skin, the infection becomes serious. The disease begins its rampage through the body in two different ways. The first, which those who have survived the illness might consider “lucky”, is if the bacteria is near the surface of the skin so that signs of inflammation are visible. This symptom usu-


ally is accompanied by a violet hue, ulcers, and black spots of the skin, which occurs about three to four days after the injury, prompting the infected patient to seek medical attention right away. On the other hand, the bacteria may have found its way deep below the superficial fascia, preventing physical symptoms of inflammation from arising and imitating flu-like symptoms such as diarrhea, fever, and general weakness. After around five days of home remedies and over-the-counter medicine without any improvement, the patient must be alarmed, as real problems may begin to occur when the disease has been given ample time to do severe damage to the body. Although Necrotizing Fasciitis is nicknamed the “flesh eating disease”, none of the bacteria actually eat human tissue. Rather, the bacteria release toxins which destroy the skin and muscle tissues. After around five days, the bacteria would have already reached this point, and tissues near infected areas might be on the brink of destruction. Antibiotics constitute the most fundamental stage of treatment, injected into the patient through needles. However, antibiotics are sometimes inadequate because the bacteria’s toxins reduce blood flow, preventing antibiotics from reaching all parts of the body. If the infected areas aren’t completely cleared of the bacte-

ria, remaining bacteria could easily reproduce and start a new infection.Under those circumstances, doctors and patients are only left with one option: to undergo surgical exploration to remove the dead tissue. If this effort fails, the patient can only resort to amputation. Center for Disease Control and Prevention reports 650 to 850 annual cases of Necrotizing Fasciitis in the United States, with a 25~30% mortality rate. Despite the deadly nature of the disease, prospects seem rather optimistic; not only have active cases reduced dramatically in recent years, but sanitary conditions have also improved significantly in many parts of the world. Improved sanitation has had a positive impact on global health and particularly, individual’s’ immune system, improving the body’s ability to fight foreign invaders like the Necrotizing Fasciitis bacteria. So as a final takeaway, everyone, it’s important to stay sanitary -- the first step to avoiding diseases like this. Even the tiniest of cuts could rapidly progress into a life or death situation.

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PRESSURE AND RELATED EXPERIMENTS BY AMY WANG ‘19

Pressure exists everywhere in our daily lives, whether we drink water with a straw, cut vegetables with a sharp knife, or cook food with a pressure cooker. In order to experience the magic of pressure, you can simply conduct the following two experiments in your dorm room—little preparation is necessary. The two experiments illustrate different mechanisms of pressure. Believe it or not, sprayers mechanisms rely on physical pressure. You can make an eco-friendly sprayer yourself with conveniently available equipment and use it to water your plants! All you need is an empty bottle and two straws. First, bend one of the straws to 90 degrees with the bending segment approximately 1.0cm. 30 • No Limits • Winter 2016

Then, cut it in half. Second, cut two holes on the cap of the bottle that has a 1.0cm distance from each other, making sure that the hole is big enough to plug in the straw. Next, insert the two straws. The top of the normal straight straw should be at the same height as the bottom of the bending part of the bending straw so that the water coming out from the straight straw will not touch but closely approaches the top of the bending straw. Finally, fill the bottle with an appropriate amount of water, enough to submerge the straight straw but leave the shorter bending straw in the air rather than water. Finally, put the cap on the bottle -- now you are done making the sprayer! Squeeze the bottle and you will see that the water from the straight straw becomes vaporous!


How does this seemingly magical phenomenon occur? We can explain this process by pressure. This sprayer uses the Bernoulli principle, which states that “for an inviscid flow of a non-conducting fluid, an increase in the speed of the fluid occurs simultaneously with a decrease in pressure.” When squeezing the water bottle, air escapes from the hole of the bending straw very quickly. The pressure of the air near the hole area becomes relatively small at this point, but the pressure of the air in the bottle above the water surface is higher . Thus the water will flow from the place of higher pressure to the place of lower pressure, thus resulting in a net flow out of the straight straw. After escaping, the liquid comes into contact with high-speed moving air coming from the bending straw. The water thus tears into tiny drops and becomes vaporous. Another interesting experiment about pressure is the Cartesian diver. René Descartes, a French scientist, created this classic experiment. Interested in creating a simplified version on your own? Follow these steps! You’ll need an empty plastic bottle and a pipet,which will be the diver. To start with, absorb some water into the pipet and leave some air in so that it can float on the water’s surface. Next, put water into the empty bottle until it is completely full. Then

put the pipet into the water bottle and put the cap on and make sure there is little air inside. Now squeeze the bottle hard. You will observe that the pipet is going down. When you release your hand, you will see that the pipet elevates to its original position again. How is this possible? The key to this mystery is the principle of buoyancy, also known as Archimedes’ Principle. According to the Pascal’s law, when squeezing the bottle, the pressure of the air increases and is transferred to water. The water is thus pressed into the pipet. The air in the pipet is compressed, and water flows into it. However, the volume of the pipet stays the same, so the gravity of the pipet as a whole is greater than its buoyancy; it thus goes down. When you release your hand, the force you put on the bottle disappears, so the volume of the air above the water surface increases, whereas the pressure decreases. The compressed air in the pipet will thus push the air out. Because the volume of displacement increases, the gravity of the pipet as a whole becomes less than its buoyancy; the pipet thus goes up and floats again. If you’d like to get to know pressure, try these two fun experiments yourself.. Mental pressure may exhaust or motivate you, but discovering pressure in physics may prove to be rather intellectually fulfilling!

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